Blow molded, tight head plastic containers are used to transport industrial chemicals. Commonly, the plastic material is polyethylene, and the containers have a capacity of five or six gallons. The industrial chemicals are typically aqueous dispersions or solutions of synthetic polymers, pickling brines, alkali cleaners, etc. When these containers are filled, they are generally stored by stacking one container upon the other, and the stack is generally supported by pallets. The stacks will often have four or more containers one upon the other. Slight upsets or misalignment during the storage of these stacked containers often causes tilting of the stack. This tilting may cause the entire stack to fall apart and can possibly lead to spillage of the contents of the individual containers. Desirably, stacks of containers should be able to remain integral even though they do suffer some tilt.